This invention relates to skimmer boats, i.e., work boats for collecting and disposing of floating solid waste materials in harbors and waterways. The invention is more specifically directed to highly maneuverable vessels equipped with means for picking up floating debris, means for storing the debris on the vessel, and means for discharging the debris from the vessel to a storage area, which may be ashore or which may be another vessel such as a barge.
Many work boats and vessels have been proposed for collection of floating solid waste and other debris. These may typically be formed as a catamaran-type hull, i.e., a pair of pontoons or sponsons, or as a monohull, with paddle wheel or screw drive propulsion, and an operator station. In one typical trash skimmer design, one or more hydraulically powered open mesh conveyors are positioned between the pontoons of a catamaran-type twin-hull vessel. Twin over-the-rear propellers are used to propel and maneuver the vessel, and these can be tipped up for cleaning weeds and debris from the propeller blades. A main pickup conveyor extends off the front end, and extends into the water to catch the floatables, which it picks up and carries back to a main storage conveyor. When the storage conveyor is completely loaded, the boat is taken to a discharge position where the debris can be transferred to a truck or barge or other facility. A rear conveyor at the stern of the craft carries the debris from the storage conveyor up and back to drop it into the barge or on-shore storage facility. In some cases, a separate, on-shore conveyor can be used to pick up the trash discharged from the vessel.
In the vessels of this type, the debris or trash is picked up and loaded from the front, and is discharged from the rear or stern of the vessel. This means that there have to be three conveyor system, i.e., a pick-up or loading conveyor, a storage conveyor, and a discharge or unload conveyor. Second, because the region of the vessel on the centerline and sternward of the storage conveyor is occupied by the discharge conveyor, the motor, the cockpit or operator control position, and any other necessary equipment have to located to one side or the other, usually atop one of the pontoons. The control position may be located on a bridge standing over the storage area.
A number of skimmer boats of various designs for collection of floating solid debris have been proposed, for example, in U.S. Pat. No. 6,669,841 to Morin, U.S. Pat. No. 5,173,182 to Debellian, U.S. Pat. No. 5,028,325 to Hamilton, and U.S. Pat. No. 3,730,119 to Budris et al.
At present, there are no skimmer boats designed for loading and discharge from the same end using the same conveyor. Also, there are no work boats in which an auxiliary portion of the hull can be added for extra flotation for the forward conveyor, and can be removed to keep the vessel narrow enough to be trucked or trailered on a roadway.